I think it all boils down to whether you want 1 program to rule them all, or to use the correct tools for the job. Option 1 leads to bloated programs such as MS Word.
When I am working, I want my favourite forceps and dissecting scissors for that particular situation. I could also say that I could hit a nail into wood with a heavy pair of pliers, but a hammer is much better.
I use DT (actually mostly DTTG) as the repository, and link into Craft, iaWriter, Numbers etc … back and forth as required
I even achieve my preferred formatting of my book annotations by moving from my epub in Marvin to Craft, then to Drafts and back to Craft by means of iaWriter.
Write once, keep the data safe (DT) and refer/use it in various formats in multiple apps